As to a method of ejecting a liquid of ink or the like, there is known a method of controlling an ejection energy generating element of a thermoelectric conversion element (heater) or the like by an electrical signal to eject liquid drops from an ejection opening of a print head.
In response to a recent demand for printing with high quality, the downsizing of the liquid drop ejected from the print head has been made. Due to the small-sized liquid drop, there is a tendency that an influence of a phenomenon where liquid drops ejected from the print head are divided into liquid drops (hereinafter, called main drops) which should be originally used for printing and side minuscule liquid drops (hereinafter, called satellites) is noticeable. For example, there are some cases where degradation of image quality is caused by the event that the satellite lands on a print medium. Further, the satellite loses its speed before reaching the print medium to be formed as floating liquid drops (hereinafter, called mists), possibly causing contamination of the printing apparatus or the print medium.
For a reduction of the satellite, for example, as described in PTL 1, it is known to shorten a length of an ink tail in the ejected liquid drop. PTL 1 discloses a technology that an ejection opening is formed in a non-circular shape, for example, in a sand clock shape to partially reduce a dimension of an opening part of the ejection opening, whereby meniscus forces are increased, which reduces stir of a liquid surface from the ejection opening to shorten the ink tail.